Question

I have this string.

$string = 'product_posting_list_name_1';

I am using this to find the match but it is not finding the match. Can anyone explain to me why? I want to match up to the last underscore and the number.

preg_match('/\bproduct_posting_list_name\b/', $string)

Answer 1

_ the underscore, is considered to be a word character, which is inside the boundaries you have placed via \b, not a boundary itself. Your regular expression is looking for complete words between boundaries, but the boundary occurs after the _1.

To match it, you cannot use a boundary on the right side.

$string = "product_posting_list_name_1";
// Replace the right-side \b with a [\d]+ to indicate 1 or more digits, followed by the \b boundary.
preg_match('/\bproduct_posting_list_name_[\d]+\b/', $string);